Calculator



3 SheetsSheet 1. B. L. DAVIS Calculator.

No. 228,448. Patented June 8,1880.

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N \Mwss as N. PETERS, PHoTo- G PMER, WASHINGTON, D C.

8' Sheets-Sheet 2. B. L. DAVIS Calculator. No. 228,448. Patented June 8,1880.

- Xmmkor M X 99W aelm 3 Sheets-Sheet 3. B L. DAVIS Calculator. No. 228,448. Patented June 8,1880.

N. PETERSJPHOTOMTHQGRAFRER. wAsHmGTON. u C.

UNITED STATES PATENT OFFICE.

BENJAMIN L. DAVIS, OF PETROLIA, ASSIGNOR OF ONE-HALF OF HIS RIGHT TO CHARLES E. SIMMONS, OF OIL CITY, PENNSYLVANIA.

CALCULATOR.

SPECIFICATION forming part of Letters Patent No. 228,448, dated June 8, 1880.

Application filed J annnry 8, 1880.

To all whom it may concern:

Be it known that l, BENJAMIN L. DAVIS, of Petrolia, in the county of Butler and State of Pennsylvania, have invented certain new and useful Improvements in Adding or Calculating Machines; and I do hereby declare that the following is afull, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make I0 and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form apart of this specification.

The invention relates to adding or calculating machines for facilitating the labor of accountants, and also to lessen the monotonous and tedious routine of adding long columns of figures.

Heretofore adding or calculating machines have been objectionable on account of their complicated construction and considerable cost of manufacturing to suit the wants of the common public.

The object of my invention is to provide an adding machine or apparatus that will meet the wants of the general accountant and combine accuracy and dispatch with simplicity of manipulation and come within the financial limits of all classes.

The invention consists of a primary wheel marked with the unit and tens numerals, and provided with a double ring of holes arranged in a zigzag manner for the insertion of a pencil or other pointed instrument for revolving 3 5 said wheel.

It further consists of a secondary or hundreds wheel provided with a circle of holes or openings for revolving said wheel by means of a latch which is operated by suitable de- 0 vices.

It further consists in the arrangement of the primary an d secondary wheels and the devices employed for operating the same and registering the proper numerals correctly when add- It further consists of the novel methods employed for returning the secondary wheel to its normal or zero position, either by means of a cord or strap around a drum secured to said wheel, or else by a suitable bit inserted into a zag manner.

slot in the end of the axle-pin of said wheel through a hole in the primary wheel.

It further consists of the peculiar construction of the cams for operating the latches when revolving the secondary wheel.

It further consists of a serrated secondary wheel and the double-latch device for operating the same.

In the drawings, Figure 1 represents a face or front view of the improved adding-machine. Fig. 2 is a front view with the dial plate removed. Fig. 3 represents the machine with the dial'plate and primary wheel removed, showing some of the operating devices. Fig.

is a vertical section of a complete machine 6 5 with some of the parts in elevation. Fig. 5 is a top view of the bed-plate removed from the case. Fig. 6 is a section of the secondary wheel and the drum. Fi 7 is a perspective view of the cam for operating the latch. Fi 8 is a perspective view of the pawl. Fig. 0 is a perspective view of the latch. Fig. 10 is a vertical section, partly in elevation, slightly modified. Fig. 11 is a perspective view of a modified latch. Fig. 12 is a perspective view of a modified cam. Fig. 13 represents a face view of a modified secondary wheel, and also of an adjustable trip-stop on the dial-ring. Fig.

14 exhibits the bed and devices as modified removed from the case. Fig. 15 represents a pencil with a point and bit for revolving the primary and secondary wheels.

The invention consists of a case, A, turned out internally for the reception of a bed-plate,

E, which is secured in said case by screws 0 e. 8 5 The case A is also provided with a projecting part, A, which is adapted to place under a column of figures when adding.

B indicates the dial or index plate, which is numbered from O to 99, and provided with a slotted opening, B, for observing the numerals on the primary plate or wheel 0, and also the sum of the addition in hundreds registered on the secondary wheel D.

The primary wheel G is provided with a 5 double ring of holes, G G, arranged in a zig- By thisarrangement of the holes they can be made of any size without cutting into each other. This wheel is also provided with an opening, 0, for returning the secondary IOO wheel D to its zero position after completing an addition. It is also provided with a hole, g, for inserting a pointed instrument for returning said primary wheel to the zero position, the pencil in hole g coming in contact with the positive stop 0, secured to the dial B. Said stop is also adapted to act in a similar manner when using any of the holes G or G, all of the above description being shown in Fig. 1.

At Fig. 13, Sheet 3, is shown an adjustable or pivoted stop, I), the object of which is to place the pencil-point in the 99-hole without moving the wheel (J before placing the pencil in said hole, and perhaps making a mistake it moving the wheel to insert the pencil in said opening, as would have to be done with the positive stop I) at Fig. 1. \Vith this adjustable stop I) it is pushed to the left hand by the pencil, as shown in dotted lines, and the pencil inserted, as previously stated. Said stop is brought to its perpendicular position by the pencil striking it on the lefthand side when arriving at the zero-point. The heel of said stop, moving on a s ud or pivot, 0 comes in contact with the checkstop I), thus offering a positive stop to the pencil when in a perpendicular position.

Secured to the wheel 0 by pins 11 is a cam, P, which is provided with a short tube, 1?, for the reception of a large screw, F, for holding said wheelUin position, and also to raise wheel 0 sufficiently high to escape the secondary wheel. This cam actuates a latch, N, at every revolution of the primary wheel, thus moving the secondary wheel D one number.

The cam P (shown at Fig. 7) is provided With an incline, 1), for raising said latch N sufficiently high so the pin N can enter one of the holes H in the wheel D, and said wheel is moved forward by means of the stud p on said cam one hole or number, after which stud 1) trips past the point it around if, when the latch is drawn against the tubecase P by means of a spring, 0, the pin N being free from the secondary wheel, as shown at Fig. 4..

The modifications shown at Figs. 11 and 12 of a latch and cam are essentially the same, the operation and devices being somewhat altered.

The latch-pin N, as shown at Fig. 10, is constantly in one of the holes of the second ary wheel, thus acting as a brake and positive stop. This latch is provided with a step-trip, h cut out of the solid metal, as shown at N and turned downward. Contiguous to said step-tripis a holder, h. As the cam P revolves, the step-trip 7L3 rides on the edge 1) of said cam until coming to the cut rim 29 when the trip is drawn into the recess of the cut rim by means of spring 0, thus moving the latch and revolving said secondary wheel one hole. As the can: moves around, the holder h (which holds the spring latch-pin N in the hole until the spring 0 has drawn the step-trip into said opening) drops into said recess by means of the resilience of said latch N, thus releasing the latch-pin N, which is driven forward by means of the swell p forcing the step-trip outward onto the edge of the rim, when it rides on the incline p and finally on the edge 1), thus pushing the latch'pin forward and into another hole, thus repeating the operation at the will of the operator.

The secondary wheel D is secured to the bed-plate E by a bolt or pin, J, entering from the under side of said bed and passing through the wheel, and furnished with a slot, j, for the insertion of a bit, when desirable to return the hundreds or secondary wheel D to its zero position. The under side of said wheel is provided with a drum, I, (shown at Fig. 6,) for winding on a cord or band, (1, provided wit-h a ring, q, for operating the same.

Secured to the bed E is a pawl-spring, K, provided with a conical point, It, for entering the holes H in said wheel 1), and holding it in position when revolving the same. By the peculiar construction of the pawl-point 7a the wheel D can be moved in opposite directions, which is necessary when returning the secondary wheel to the zero position.

Secured to bed E by a screw, Z is a friction brake and stop, L, and held in position by a pressure-phi, l, and spiral spring I. The end of said friction-brake enters a detent or notch, (I, when the zero comes opposite the slot B in the dial-plate or ring D.

The modification shown at Fig. 10 is provided with a stop, d, by means of a pin, d, in the secondary wheel coming against said stop. This wheel D dispenses with the spring-pawl K and friction-brake L, they being substituted by the latch-pin N, constantly in one of the holes H, and also by the friction or pressure springj on the back of plate E, and secured by a split wedge, 9' entering an annular recess, j, formed in the end of the axle -pin J, as shown in dotted lines at Fi 14-.

The arrows z and 2 indicate the zero-point, and also the direction the primary wheel is rotated.

The wheel 0 at Fig. 13 is rotated in an opposite direction. to the one shown in the preceding figures.

The modification shown at Fig. 14 is provided with a serrated secondary wheel, D, and is actuated by a double latch, R and B, and a positive spring, S. As the cam P rotates, the trip 1" enters the recess 11 in said cam, thus driving said wheel D forward one tooth by means of the latch It. As the cam continues to rotate it forces the latch R on the periphery p of said cam, thus repeating the operation. When the latch It is returning to the position as shown in the modification, the latch R turns on a pivot, 1", allowing the end 0' to drag 011 the under or inclined edge of the adjacent tooth to be next moved forward until it passes the point of said tooth, when the latch It is drawn down against the positive stop-pin r by means of the spring 1*, thus forming a rigid stop for the latch B after it has passed the point of the next adjacent IIO tooth, when it is in position to move the sec- 1 ondary wheel another tooth or number at the will of the operator.

In operating my improved adding-machine it is first necessary to bring the three 0 0 Os opposite the slot B in the dial-plate B. This is accomplished by placing a pencil or other pointed instrument into the hole 9 (indicated by the arrow 2) and turning the primary wheel 0 until the opening 0 comes directly over the slot j in the pivot or bolt J, passing through the secondary wheel D, when said wheel D is returned to the zero position by inserting a bit into said slot j and turning toward the right hand, or else return said wheel to its zero by pulling the cord or tape q by means of the ring q, after which place the pencil again into the hole 9 and return said wheel 0 until the pencil comes in contact with the stop I), as shown in Fig. 1, when the three 0 0 Os will appear at the slot B, when the machine is in a position to commence adding. By placing the pencil-point into any of the holes G or G, and turning or carrying said wheel 0 around until the pencil comes in contact with stop I), the sum of the addition will appear on both wheels O and D through the slot 13, as heretofore stated.

Having described my invention, that which I claim as new, and desire to secure by Letters Patent, is-

1. The arrangement of the primary and secondary wheels 0 and D, provided with a double ring of holes, G and G, and hole or opening a, substantially as shown and described.

2. The secondary wheel D, provided with holes or openings H, for moving the same, and a latch, N, pivoted to the frame at one end, in combination with a cam, P, and a wheel, 0, for giving the sum of numbers, substantially as shown and described.

3. In an adding-machine, the combination of a hundreds-wheel provided with a drum, a spring-pawl, K, friction-brake L, strap I and q, for returning said wheel to its zero position, and operated as shown and described.

4:. In combination with a hundreds-wheel, a double-acting pawl, K, and a friction-brake, L, and operated substantially as shown and described.

5. In combination with the dial or face of an adding-machine having a series of holes arranged zigzag therein, a pivoted stop, I), for arresting the movement of an instrument when actuating the primary wheel by means of the holes Grand Gr, substantially as shown and described.

In testimony that I claim the toregoing as my own I have hereto affixed my signature in presence of two witnesses.

BENJAMIN L. DAVIS.

Witnesses U. D. W. LILLIENDAHL, W. It. EDELEN. 

